Thus a receptor may be a protein, enzyme, membranechannel, or a region of a foreign pathogen.
这样的受体可以是蛋白质、酶、膜通道或外来病原体的一个区域。
2
An ion channel is a molecule that allows the passage of electrically charged atoms of sodium, potassium, calcium and so on through the outer membrane of a cell.
离子通道是一种分子，它允许钠、钾、钙等离子经由它通过细胞外膜。
3
The resulting channel enabled them to move both single - and double-stranded DNA through the membrane.